Selective signaling system.



vJ. C. FIELD. SELBGTIVE SIGNALIN'G SYSTEM.

APPLIOATION FILE-D AUG. 23, 1912.

F y /m/emo/f. L/osephOF/e/d. wb by rso JOSEPH c. FIELn, OF ORANGE, NEW/JERSEY, AssIGNon To' WEsTERNf nnnoirnie I COMPANY, Or'Nnw YORK, N. Y., n CORPORATION OF ILLINOIS. A

sELEoTIVn sIeNiulINe srsTEM.

To czZZ whom t may/concern:

Be it known that I, Josnrn C. FIELD, a citizen of the United States, residing at Orange,-in the county of Essex and State of New Jersey, have invented a certain new and useful Improvement in Selective Signaling Systems, of which 'the following is a full, clear, concise, and exact description.

This invention relates to selective signaling systems of that class comprising a sending station and a plurality of way stations. `each way station being equipped with selective apparatus responsive to a predetermined character or combination of current impulses, sent out 'from the sending' station, to operate a local signal.

The Object of the inventionis to.provide 'means in connection with such a system for impressing impulses upon the line of a Acharacter to operate a signaling device connected -in series with the selector without effecting' ythe operation of the selective apparatus or interfering 'with any conversation which might be taking place asthe-signallng 1mpulses are beingsent out.

Theprincipal feature of this invention is the provisiony -Oi a condenser` ,combination by meansof which time sending impulses from a telegraph lline will, with. the same battery supply as is used to operate vthe selectors,` impress upon the line, potentials ol.. alternately oppositepolarity approximately l' twice the potentialof the. sourceof supply and will cause such a gradual ,emission and extinction of the current impulses that telephonic'apparatus will be unaffected thereby.

In accordance'with this invention there is providedxat `the sending stationa pole changing relay operating in response to impulses oyer a telegraph` line or 'other vextraneoussource to connect a sourceof cur- -rent with the line wires and two condensers, one connected in bridge of the line wires 'to discharge through the signal ydevice prolong the.. impulse caused by the ,discharge of the other which is associated with ,the contacts of the polechanging frelay in,I such manner ,as to be alternately discharged and charged to produce a momentary i'mnl'llse greater `than thenormal battery yoltage.

In the drawings illustrating tl is invention-Figure 1 is a diagramv offtie apparatus ,and connections of straight train ydespatching,scheme embodying tinsI invenl-14C and 15.

over the line `wires and through the signal n Y i Specication ofLvettersiPatent. i y Patented J 11.26;?1915,

` v Application filed August 23, 1912. Serial No. 716,644. I

'vratus and connections of an intercommunil eating train despatching scheme lembodying this invention. f

In the two iigures of the drawing l and 2 design-ate the line wires, A the despatchersstation and B and C way-statlons-on the line. Connected1 in the liney wires 1 and 2 are retardation coils 3 and '4 operating in conjunction vwith la condenser 5 65 bridgedacross the line wires to smooth: out or graduate the current impulses' transmitted for operating' they selector so that,v v they will not affect telephone v'apparatusl which may be connected with-the line ldur ing the operation yofa selector-. l v

Located at eachk of the waystations lisa selectorl mechanism comprising l slowp andv quick acting magnets 11 and -12,.,2'1nd.. ai' .ratchet wheel 13 .controlled thereby:` through 75 ther medium of stepping and holdin'gxpawls Attached to the ratchet vwheel- 13 is a contact arm 16 adaptedin. the Ita-Q.l tion of said ratchet wheel tozbe"'brouglit into Contact with' the anvil 17 to complete .a'circuit through a vibrating bell 18forf1sirnal-- ing the waystationoperatoinll The rline wires land 2 Ol:"e'aC Schemenre 1;. connected with the studs otra/double poleflfis double throw lswitch 20. the other "studs-of 85 which are connected with contacts,.ofa.,im pulse relay 21 and a jpolefchangingjrelay 22 respectively. Inthe' 'scheme shown. Fig( 1,'one pair lofthe studs of the switch t 20 is connected directly with. normally open -90 `contacts of theimpulse lrelay y2l, tliefarmature levers 23 and' 24 .of which vare` connected with the oppositegpoles ofa battery 25.'. An impulse transmitter 2,6 with acon-21?:` denser and a Vresistance `in shunt withthe 95. impulse `relay 21'anda local battery 27 is adapted to; intermittently close Ythecircuit through 'they relay 21 tol send-impulses over the lineior operatingfthe selectors.l` .-j...

;In they scheme yshown in'vF,'g.'2 ifthezjim-' 100 pulse 4relay is adapted-to bepperafd from any one of the ,sending stations llby'means of a keyBO arranged to connect ground' with both of the line wires. For: thispur-L pose the line wires 1 yand 2 are connected 105 directly with thewinding4 loi the impulse relay 21 through'a's'ource of current 25 and the impulse relayisl provided with contact 31 and armature. 32 Aoperatingwhenf'vthe one ofthe' line-wiresand connect the source operated. fromr a local .transmitter key 33.

The pole changing relay .22 in both vschemes isssconnected in circuit' with the source of,

energy through a contact 38 on a relay r .gthe'winding'of -which isl connected in Acircuit to respondto impulses-over a telelic which time impulses are sent from the Na'-` than thatI of the Vcondenser 55 depending graph :line 'oral standard time wire over onalj Qbservatorv at ,Washington, D. C.

ries. withth'e selector magnets 11 and 12.

ringer operates in response to alternating current impulses over theline wires 1 '.-1and12-.a'nd in consonance with the relay 39.. 20.v 'l "4V-ing lmpulses to which the ringers respond is as fol-lows: Y 7

The arrangement for sending the alternat- A'sshown the contact armatures 45 and 46 'v of thefpolle changing relay 22 are connected energy25 and eachis adapted to make and break a pairpf contacts 47,- 48, and 49, 5,0 respectively lto :connect a condenser 55 inf v'with thel opposite poles of the source of .series with the sourceofcurrent 25. The

condenserv 55 .is so arranged that it will first be'chaprged to the'ull potential of the bat ltery 25 vin one direction through the contacts 47- and 49;.-5 Upon reversallofthe battery by the operation ofthe -relays 39 and 22 the condenser 55 is discharged through. the signalj40. in series with .the source 25 and. chargedvin the opposite directionv to they full potential of the battery-25 through the contacts 48 and'50, thusgiving the equivvalent of twice'the voltage lof the battery l 425"for" seijiding-. the reversed lcurrent iml pulses over the n line. The condenser 5 across the line at the sending end is charged on each reversal, off the. sending battery but only remains charged until the condenser tin serieswith the line has become fully charged.- When this occurs there isino current flowing, the potential across the line becomes zero and the condenser 5 across the line will discharge and send current out'l over the line in the Same 'direction as 'the last impulse due Jto the charging Vofthe condenser 55 in series with the line,' `This discharge of condenser 5- 'tends to prolong each current impulse 'sent' "pover the` line and't'hrough` the ringers. vThis nectthe line vwires 1 and2'with .the contacts may bemore clearly-seen by tracing in del tail the paths of the currents ,whlch are as y follows: Assuming that the 'switch 20V is thrown to the right or into posltlon to conofftlie' relay v22. If ,the relay'22 is denererheen .se ..22

l "gizeclzv there willvbe a` path' for current'as V{nl ldws from the minus Iside `o ffthe -L battery Located vat ,each of the waystations is al noir-biasedjf polarized ringer 40 which 'is- .Lbrrdged Iacross the line wires l and 2 in seblade of the switch 20, conductor'2, parallel' paths one of which includes the condenser 5 and the other the selector bridge, includa condenser 55 'to practically the normal voltE age, -the condenserp to possibly half or less upon the impedance of the selector bridges.

a As the condenser 55 becomes charged, how-l ated to close the circuit of the relay 22 to' open the contacts 47 and49 and close the contacts 48 and 50, there will vbe completed a' discharge path for the condenser 55 which may be traced as .followsz ffrom the minus side of the battery 25 through contact 50, condenser 55 one blade of the switch 20, 'linelwire 1 the bridge including the electromagnetsll and 12 andthe ringer 40,-line wire .2, the other blade of the switch 20, contact 48 of the relay 22 to the plus side oi' the battery. This will give a momentary surge of current over the line wires and,

through the vcondenser 5'- and the selector bridges of a total equal to the amount of,

thecharge on the condenser. 55 andthe volt` age of the battery 25. As sc on as this momentary surge has ceased and the condenser.; 55 has entirely discharged it will chargeV in the opposite direction. When ithas beccnnev charged and no current is flowing the condenser 5 will discharge over the line Wires 'in the direction of the last charging impulse of the battery 25, thus prolonging the current impulse through theringer 40. Similar operations will follow each operation of the relay 22 and 'reverse current impulses of equivalent to practically' twice the volt age of the battery 25 will be sent over the line wires through the ringer 40 whichA will tap one of its gongs for each reversal. v

With a scheme such as hereinbefore de scribed there is but a very low intermittent 'current drain upon the 'sending battery.

while sending time. n

The cost of additional apparatus for equippinganyyline is very slight and may be' ,added to any existingcircults without change andlconversation may be carried on yovera linesoequipped 4if desired while time als are being sent.-y f claim: f

1. In a selectivevsignaling system, line 'connected therewith, a source of current at said sending station, means thereat for send; ing current impulses, a selector at said way station including a slow acting holding-magnet responsive to current impulses, a polarized signaling device at-said way station in bridge ofsaid line wires andin series with said slowacting holding magnet,reversing means at, said sending'. station for applying current 'from said source to said line alternately in'oppo'site directions, and-means at said sending station alternatelyv charged and discharged 1n the operation of said reversing means for operatlng' said polarized signal and preventing the operation of said slow acting holding magnet..

2Q In a 'selective signaling system, line wires, a sending stationand a'way station connected therewith, a source of current at said sending station, means thereat for sending current impulses, a selector at -said'vr'ay station including a slow acting holding. mag-A to current impulses', a polardevice at said way station in bridge of said line Wires and in series with said slow acting holding magnet,' rever sing means at said sending station for applying current from said source toisaid linewires a-lternately in opposite directions, and acony denser at said sending station connected with said line 1n the operation of said reversing means and alternately charged and discharged said polarizedsignal and preventing the operation-of saidslow acting holdingmagnet.

at each reversal for' operating 3. In a selective signaling system,A line-- wires, a sending station and afway station connected therewith, a source of current at said sending station, meansthereat for sending current impulses, a selector at said Way station including a slow net responsive to current impulses, a polarized signaling device at said way station'in bridge of said line wires and inseries with said selector, reversing meansl at said sending station for applying current from said s'ource tosaid line alternately in opposite directions, and a condenser in series with said line wires at said sending' station alternately charged and discharged .in the'operation of said reversing. means for giving momentary Jdischarges over said line -wires whereby 'said vpolarized, signal' is operated andthe operation of said slow acting 'magnet .is prevented.' v

whereof', I'hereunto subscribe Inll witness my name this`122nd day of August, A.' D. 1912.

Witnesses: l

WALTER F. HQFFMAN, ELLA EDLER.

acting holding magv JosErH o. FIELD." i 

